Posted on January 02, 2015 at 18:32Hello,
I've test the STM32F303 for using it in a new project. The configuration and libbrary are used from the CubeMX with the IAR compiler.
Now I can maximum transmit 4 bytes over the UART with one DMA transfer.
Here my configuration for the DMA and UART:
huart2.Instance = USART2;
huart2.Init.BaudRate = 57600;
huart2.Init.WordLength = UART_WORDLENGTH_8B;
huart2.Init.StopBits = UART_STOPBITS_1;
huart2.Init.Parity = UART_PARITY_NONE;
huart2.Init.Mode = UART_MODE_TX_RX;
huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart2.Init.OverSampling = UART_OVERSAMPLING_16;
huart2.Init.OneBitSampling = UART_ONEBIT_SAMPLING_DISABLED ;
huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
hdma_usart2_rx.Instance = DMA1_Channel6;
hdma_usart2_rx.Init.Direction = DMA_PERIPH_TO_MEMORY;
hdma_usart2_rx.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_usart2_rx.Init.MemInc = DMA_MINC_ENABLE;
hdma_usart2_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
hdma_usart2_rx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
hdma_usart2_rx.Init.Mode = DMA_NORMAL;
hdma_usart2_rx.Init.Priority = DMA_PRIORITY_LOW;
HAL_DMA_Init(&hdma_usart2_rx);
__HAL_LINKDMA(huart,hdmarx,hdma_usart2_rx);
hdma_usart2_tx.Instance = DMA1_Channel7;
hdma_usart2_tx.Init.Direction = DMA_MEMORY_TO_PERIPH;
hdma_usart2_tx.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_usart2_tx.Init.MemInc = DMA_MINC_ENABLE;
hdma_usart2_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
hdma_usart2_tx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
hdma_usart2_tx.Init.Mode = DMA_NORMAL;
hdma_usart2_tx.Init.Priority = DMA_PRIORITY_LOW;
HAL_DMA_Init(&hdma_usart2_tx);
__HAL_LINKDMA(huart,hdmatx,hdma_usart2_tx);
I start the transmission with the function HAL_UART_Transmit_DMA (&huart2, pData, uSize);
When I call this function with uSize 1,2,3 or 4 works all fine. All values bigger than 4 have the same result as 4.
Have somebody a idea?
Thanks,
Bernd
